The present invention relates generally to oral devices and particularly to a device for improving the breathing of a user.
It is known that the mandibular advancement to help with obstructive breathing disorders has been used successfully. Applications are known for sleep apnea and snoring. Therapeutic successes have been achieved, especially with such devices with rails for the upper and lower dental arch which are custom made for the user.
Such systems require coupling elements between the two rails, which cause the mandibular advancement required by the therapy. Many embodiments of these coupling elements are possible.
Devices that are worn inside the dental arch influence the users comfort, disrupt the speech and the swallowing and can lead to increased salivation. Examples of such models with coupling elements inside the dental arch are described in DE20319088U1 and EP1312319A2.
Other devices with arrangement inside the dental arch and labial, are shown in DE 69501111T2, WO 2005013867A2, and U.S. Pat. No. 6,305,378B1 and allow only a small opening of the mouth. Where adjusting devices are proposed for the advancement, they cause additional deterioration of wearing comfort, as they occupy a portion of the tongue space. Because the tongue cannot reach the lips, the user cannot moisturize the lips with his tongue. Therefore, an important feature for the wearer's comfort is missing.
The arrangement of the coupling elements outside of the dental arch, as well as labially, allows little mouth opening, as shown in DE112009001742T5. Moreover, the mouth cannot be completely closed, which leads to undesired mouth breathing. Thus, speaking is impaired, as the tongue cannot reach the lips and the user cannot moisturize the lips with his tongue.
Coupling elements labially arranged outside of the dental arch need less space, as shown in DE 102008007281A1, as long as a complex adjusting device for the advancement is absent. A coupling element between the two rails is a curved guide member, whose ends are connected with both sides of the second rail. The opening of the mouth is limited. When trying to open the mouth further, forces result which remove the rails from the dental arches. That way the effect of the system is lost.
A frequently proposed arrangement of coupling elements uses two coupling elements and four joints buccally outside of the arch.
Tensile forces for advancement are acting within the coupling elements in devices according to CA 2694017, DE 202007007760U1, DE 000029506512U1, and DE 202008011841U1, because they connect the anterior region of the maxillary rail and in the posterior region of the mandibular rail. The coupling elements are partly designed as rigid rods, partly elastic, and like a telescope, are partially adjustable length by spindle mechanics.
Such solutions are bulky, and therefore not very comfortable to wear, are not easy to clean, are mechanically relatively complex and are expensive to produce. The mentioned devices with tensile force transmission kinematics lead to increased advancement of the mandibula when opening the mouth. This can lead to a locking situation, i.e. the mouth cannot be opened above a certain aperture. When trying to open the mouth further, resulting withdrawing forces would remove the rails from the dental arches. In this manner, the effect of the system would be lost. Attempts have been proposed to resolve these drawbacks by providing variable-length coupling elements. Nevertheless, it is uncomfortable for the user when the opening of the mouth is prevented or impeded.
A compressive force is transferred through the coupling elements in the devices according to EP1972311A1, EP2081525B1, U.S. Pat. No. 6,012,920, U.S. Pat. No. 6,526,982B1, in which the coupling elements connect in the posterior region of the maxillary rail and in the anterior region of the mandibular rail. With this arrangement, the opening of the mouth is easier and less limited. The kinematic effect during opening causes a reduction of the advancement of the mandible. The buccal arrangement of the coupling elements causes their short length. A coupling element describes a circular arc about the pivot point on the upper jaw rail. Because the circular arc has a small radius even at a relatively small angle, a remarkable loss of advancement is the result. To correct this shortcoming, in EP1972311A1, length adjustment with telescope and spring is proposed. However, since the spring force results in an undesirable mouth opening, a closure device is also necessary. This keeps the mouth shut, but results in loss of the freedom of mandibular movement. The user gets a feeling that the jaw is locked.
Further devices, such as that described in DE 102007050309B3, have two coupling elements, which are fixed only at the posterior ends of the upper and lower jaw rails. They have no joints, but are rigidly connected to the rails. They respond by elastic deformation on opening the mouth. This also leads to a restriction of the mouth opening and causes withdrawing forces on the rails.
A similar solution is proposed in DE102008051221A1. It corresponds to the structure of the above solution, but provides one additional joint for every side in the coupling element. In principle, the kinematics is the same as for models without a joint. Here too, with jaw movement, forces attempt to remove the rails from the dental arch.
All known devices only partially fit to the requirements for the successful spread of mandibular advancement.
Existing deficiencies are: lack of comfort while wearing such rails; lack of free lateral and sagittal movement of the mandible; lack of freedom of tongue space; obstacles to closing the lips; no, or cumbersome, tunability of the advancement by the user; limited longevity because of sensitive precision mechanics; difficult maintenance due to complicated shapes; and high production costs due to expensive, complicated items.